Hitachi Universal Storage Platform VM - Manual (Page 85)

Functional and Operational Characteristics 3-41
Hitachi Universal Storage Platform V/VM User and Reference Guide
Detection of Power Failure
AC Input Power Failure Occurs
1 minute
Storage
System
Operating
8 minutes
Data destage process
Power off process
5 minutes
24 hours (CM up to 128 GB)
18 hours (CM 132 GB to 256 GB)
CM and SM are backed up by battery.
200 ms
Storage
System
Operating
CM and SM are backed up by battery.
Ç *2
Destage Mode
USP V only
(battery option
required)
Ç *1
Backup Mode
USP V/VM
Power Failure
Power Failure
Universal Storage Platform V:
48 hours: CM up to 128 GB
36 hours: CM 132 GB to 256 GB Universal Storage Platform VM:
36 hours
Notes:
1. When power is recovered after a failure while backup power is being supplied by battery, the storage system
operates depending on the status of the Auto-Power-On JP on the Operator panel:
ENABLE: The storage system is powered on automatically.
DISABLE: The storage system is powered on by operating the Power ON/OFF switch or the PCI.
2. When power is recovered after a failure during the destage process, the destage and power-off processes are
executed.
Figure 3-6 Battery Backup Processes for Power Failure